Some retailers are seeing double the number of pre-orders for next-generation consoles as they have for the previous launch

With roughly 4 months still to go, some retailers are reporting that pre-orders are twice as high as last-gen (PS3, X360) consoles.

Could this mean the gaming community has expanded vastly since the current-gen launch? Maybe Wii U flop has pushed Nintendo gamers towards PS and Xbox?

Yes for both I believe. The Wii was successful because it was cheap and it brought in something which was new and exciting (Motion Controls).

Its no longer so cheap and the motion controls aspect has been surpassed by both the PS and Xbox. It also brought in something no one wanted, a giant gameboy-like controller.

For the gaming community expanding its maybe because of products like the Wii bringing in more casual gamers, or smartphones like the iPhone bringing in even more casual gamers. Regardless of the cause the evidence is clear, Everyone's a bit of a gamer, be it COD or Candy Crush, BF or Just Dance, maybe even GTA or Solitaire; Gaming is bigger than it ever was and is still getting bigger.

I think it's also because there is now a whole new older generation interested in gaming. People who grew up with computer games there from the start are now the people who have jobs and do what they want, while the younger generations (who rely on their parents/summer jobs) interested in consoles probably also grew. I just think there's a bigger market for them in general.

Like above, I've pre-ordered both and can easily afford to pick up both at launch even though it will be well over $1,000. Last gen the consoles where more expensive ($1,000) just for the PS3 and being only 16 presented many a problem for people who grew up with consoles.

I think the push is mainly console generation being able to afford what used to be targeted towards people a lot younger.